WASHINGTON -- Experts predicted yesterday that a recent, unprecedented emphasis on teaching reading across the country would produce significant gains in American students' test scores.

But that was not directly evident in the results released yesterday from the most recent national reading assessment.

The National Assessment of Educational Progress "reading report card," released by the U.S. Education Department, showed small increases in all three grades tested -- with eighth-graders posting the most gains.

But about a third of the 500,000 students tested nationally did not reach the "basic" level on the assessment, defined as reflecting partial mastery of reading at grade level.

NAEP is the only national test of students' reading skills. Officials said a state-by-state breakdown of the results would be released late next month after a computer error is corrected.

The small gains on the NAEP test last year are consistent with those achieved by Maryland students in grades three, five and eight in the 1998 round of the state's reading tests.

U.S. Secretary of Education Richard W. Riley and Mark D. Musick, chairman of the NAEP governing board, predicted yesterday that there would be a significant upturn in scores when the test is administered next, in 2000.

Musick and several other officials also remarked on what he called "unprecedented" reading emphasis these days at the federal, state, community and school levels.

"Pick nearly any state," he said. "You need only look next door to Maryland. If you talk to either Gov. [Parris N.] Glendening or state Superintendent Nancy Grasmick for two minutes and they don't mention reading, I will be surprised."

Musick noted that reading is a "bipartisan issue," championed by Republican governors in Texas and West Virginia and Democrats in North Carolina and California.

In Annapolis to lobby for teacher-hiring incentives, Grasmick agreed.

"A lot of things are working in tandem right now," she said. "If you had asked a group of educators 20 years ago what was their most urgent challenge, they'd have said reading, but nobody would have done anything about it. That's changed dramatically."

Grasmick said she did not know how Maryland fared in the 1998 reading assessment, but she predicted little improvement over 1992 and 1994 assessments. "It takes time," she said. "My optimism is for the next round."

As if to emphasize the urgency of reading, yesterday's news conference also was attended by Vice President Al Gore. Neither he nor the secretary of education attended the equivalent event four years ago, and a vice president has never helped announce assessment results.

Gore put in a plug for President Clinton's education initiatives, including the president's proposal to reduce class sizes in the early grades and his proposed increases in the Reading Excellence Act for teacher training and tutoring.

"Virtually every child can learn to read," said Riley. "If children cannot read, it is not because they have failed. It is because we have failed them."

Among the findings of the NAEP report:

Fourth- and 12th-grade scores were essentially unchanged, while eighth-graders showed a little more progress -- contrary to the drop-off in eighth-grade test scores on Maryland's own reading tests.

Only a third of students scored at the "proficient" level, essentially at or above their grade level. The percentage of "advanced" readers was stuck in the single digits in all three grades, as it has been through this decade.

Fourth- and eighth-graders in the Northeast and Central regions outperformed their counterparts in the Southeast and West. Among 12th-graders, students in the Southeast had lower average scores than those in other regions.

Across the nation, females and nonpublic-school students had higher reading scores than males and public school students.

In fourth grade, the small increase in scores was evident primarily among lower-performing students. The eighth-grade increase was seen primarily among students in the lower and middle levels of performance.

The percentages of students who reported watching the most television -- six or more hours a day -- decreased since 1994 in all three grades. Eighth- and 12th-graders read more pages daily for school and homework than in 1994.

Students in all three grades are being given more time in school to read books of their own choosing.

To judge motivation, the assessment asked students if they thought it was important to do well on the test. Eighty-six percent of fourth-graders thought doing well was important, 58 percent of eighth-graders wanted to do well, but only 31 percent of 12th-graders were motivated.

In all three grades, there were no achievement differences between African-American and Hispanic students with one exception: The percentage of Hispanic 12th-graders at or above proficiency was higher than that for black seniors.

The modern version of the assessment was first administered in 1992; but as a backup, officials have given the 1971 version to a smaller sample of students nine times over the 28 years. In nearly three decades, scores have hardly budged.